68 Proceedings of the Biological Society of Washington. 



Diagnosis. — Differs from Echiothrix leucura and E. centrosa in smaller 

 size; smaller hind feet; much more vinaceous, less buffy or yellowish, color- 

 ation; darker underparts, buff or reddish-buff rather than yellowish or 

 whitish; and smaller, less narrowed skull. Ears and teeth small, as in 

 centrosa. 



Measurements. — Type: Head and body, 198 mm.; tail, 240; hind foot, 

 48; ear from notch, dry, 28.1. Skull of type: Condylobasal length, 48.7; 

 zygomatic breadth, 23.7; palatal length, 27.8; breadth of braincase, 19.0; 

 interorbital breadth, 6.9; orbit to end of nasals, 23.1 ; mandible, 28.2; upper 

 tooth row, 6.5; lower tooth row, 6.5. 



Specimens examined. — Thirteen from the type locality. 



Remarks. — This species is easily separated from E. leucura and E. cen- 

 trosa by its small size, peculiar coloration, and the less narrowed skull. It 

 has small ears and small teeth as in E. centrosa. 



Rattus musschenbroekii tetricus, subsp. nov. 



Type from Gimpoe (southwest from Lake Lindoe), Middle Celebes. 

 No. 219,613, U. S. National Museum; skin and skull of adult cf (teeth 

 moderately worn); collected August 27, 1917, by H. C. Raven; original 

 number 3184. 



Diagnosis. — Like Rattus musschenbroekii musschenbroekii Jentink from 

 North Celebes (Menado) ; but larger, with longer tail and hind foot; general 

 color of upperparts much more reddish, less buffy; skull larger, with more 

 robust teeth. 



Measurements. — Type: Head and body, 160 mm.; tail, 145; hind foot, 

 34. Skull of type: Condylobasal length, 35.0; zygomatic breadth, 16.7; 

 breadth of braincase, 15.1; interorbital breadth, 5.9; mandible, 20.8; 

 maxillary tooth row, 6.1; mandibular tooth row, 6.1. 



Specimens examined. — Ten, all from Middle Celebes; Gimpoe, 1; Pine- 

 dapa, 7; Rano Lindoe, 1, Rano Rano, 1. 



Remarks. — Two well marked forms of Rattus musschenbroekii are included 

 in the collection. The typical form is represented by more than 70 speci- 

 mens from localities in North Celebes. Compared with these, the small 

 series of skins and skulls from Middle Celebes is conspicuously different, 

 the specimens averaging larger and much more reddish, with larger, 

 especially longer, skulls and with larger teeth. 



Rattus raveni, sp. nov. 



Type from Toll Toh, North Celebes. No. 199,976, U. S. National 

 Museum; skin and skull of adult c? (teeth moderately worn); collected 

 December 16, 1914, by H. C. Raven; original number 1963. 



Diagnosis. — A large, light colored member of the Rattus concolor group. 

 Upperparts grizzled ochraceous tawny; the longer, soft hairs tipped with 

 buckthorn brown; the spiny hairs grayish buff, with blackish tips; hind 

 foot creamy buff, sometimes with a faint line of dark extending down from 

 ankle. Differs further from specimens of the concolor group from Sempang 



